Federal law enforcement officials are reportedly investigating several threats against U.S. lawmakers ahead of the Senate impeachment trial of former President Trump. 

A source told The Associated Press that the threats have been made in chat rooms and on online message boards in recent days. The threats, which vary in credibility and specifics, include plans to harm members of Congress during travel to or at the U.S. Capitol, the source said. 

Trump was impeached by the House earlier this month following a deadly riot by his supporters at the U.S. Capitol, and a Senate trial is slated to begin on Feb. 8. 

The siege led to the deployment of tens of thousands of National Guard troops to Washington, D.C., ahead of President Biden’s inauguration, an event held largely virtually and without reports of violence. 

Separately, local police in Washington, D.C., and federal Homeland Security officials have said they are aware of ongoing chatter among far-right groups to hold future armed protests in or around the Capitol. 

That chatter, coupled with threats against lawmakers, have led U.S. Capitol Police to ask the National Guard to leave several thousand troops in D.C. in the coming weeks, the AP reported. 

The news service estimated all but about 7,000 guard troops will leave the nation’s capital with some Guard presence expected to remain in D.C. through mid-March. 

Trump is the first president in history to be impeached twice and is the first to face a trial in the Senate after leaving office. 

Senate Minority Leader Mitch McConnell (R-Ky.) has promised Republicans will participate in an orderly and thorough trial after several of his House colleagues accused Democrats of pushing forward with a “snap” impeachment. 

“Given the unprecedented speed of the House’s process, our proposed timeline for the initial phases includes a modest and reasonable amount of additional time for both sides to assemble their arguments before the Senate would begin to hear them,” McConnell said last week. 

Trump faces one article of “inciting insurrection” over his remarks to supporters before they attacked the Capitol. He told them to “march” on the building and display “strength” as a joint session of Congress met inside to certify Biden’s election win. 

Trump refused to concede he lost the presidential election, peddling unproven claims about voter fraud and falsely stating the election was “stolen” from him and his supporters.